/*
 * Copyright 2002-2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.web.bind.support;

import org.springframework.lang.Nullable;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.context.request.NativeWebRequest;

/**
 * Create a {@link WebRequestDataBinder} instance and initialize it with a
 * {@link WebBindingInitializer}.
 *
 * @author Rossen Stoyanchev
 * @since 3.1
 */
public class DefaultDataBinderFactory implements WebDataBinderFactory {

    @Nullable
    private final WebBindingInitializer initializer;


    /**
     * Create a new {@code DefaultDataBinderFactory} instance.
     *
     * @param initializer for global data binder initialization
     *                    (or {@code null} if none)
     */
    public DefaultDataBinderFactory(@Nullable WebBindingInitializer initializer) {
        this.initializer = initializer;
    }


    /**
     * Create a new {@link WebDataBinder} for the given target object and
     * initialize it through a {@link WebBindingInitializer}.
     *
     * @throws Exception in case of invalid state or arguments
     */
    @Override
    @SuppressWarnings("deprecation")
    public final WebDataBinder createBinder(
            NativeWebRequest webRequest, @Nullable Object target, String objectName) throws Exception {

        WebDataBinder dataBinder = createBinderInstance(target, objectName, webRequest);
        if (this.initializer != null) {
            this.initializer.initBinder(dataBinder, webRequest);
        }
        initBinder(dataBinder, webRequest);
        return dataBinder;
    }

    /**
     * Extension point to create the WebDataBinder instance.
     * By default this is {@code WebRequestDataBinder}.
     *
     * @param target     the binding target or {@code null} for type conversion only
     * @param objectName the binding target object name
     * @param webRequest the current request
     * @throws Exception in case of invalid state or arguments
     */
    protected WebDataBinder createBinderInstance(
            @Nullable Object target, String objectName, NativeWebRequest webRequest) throws Exception {

        return new WebRequestDataBinder(target, objectName);
    }

    /**
     * Extension point to further initialize the created data binder instance
     * (e.g. with {@code @InitBinder} methods) after "global" initialization
     * via {@link WebBindingInitializer}.
     *
     * @param dataBinder the data binder instance to customize
     * @param webRequest the current request
     * @throws Exception if initialization fails
     */
    protected void initBinder(WebDataBinder dataBinder, NativeWebRequest webRequest)
            throws Exception {

    }

}
